1. Field of the Invention
This invention is generally directed to wood chipping, shredding and pulverizing machines and, more specifically, to a trailer mounted shredding machine for reducing waste timber, logs, lumber, tree limbs, roots and other wood fiber debris into a shredded mulch-like consistency. The shredding machine of the present invention incorporates an auger having a generally continuous flight wherein cutting teeth are mounted so as to form portions of the flight. The cutting teeth of the auger cooperate with replaceable anvil teeth which are mounted so as to form a portion of a semi-circular conveying drum which extends the length of the auger. The auger teeth not only serve to shred material being processed but also act, with the remaining portion of the auger flight, to convey the material to an axial discharge opening. Processed materials are discharged from the discharge opening onto an elevating conveyor. The elevating conveyor is pivotably moveable from a vertical travel position to a second working position and is driven by a friction drive element which engages the output end of the auger drive shaft.
The auger of the present invention is preferably driven by a hydraulic motor which is controlled by suitable hydraulic pumps driven by a gasoline or other motor source housed on the trailer.
2. History of the Related Art
In view of the ever increasing problem of waste disposal, it has become paramount that various waste products be processed into usable or recycled materials. In this respect, landfills in many areas have begun rejecting the disposal of various types of materials including grass clippings, pruning debris, and timber cuttings including trees and tree roots. In other landfills, special processing centers are provided for reducing organic fibrous materials including branches, tree trunks, tree root systems, discarded lumber and the like into a shredded material which may be utilized as a mulch. In addition to the foregoing, in some localities, shredded or processed wood fiber material is blended with other additives including waste manures to create potting soils and other organic medium for use in agriculture.
Unfortunately, not all areas have the facilities adequate to convert waste organic fibrous materials to useful products. Further, the use of centralized collection facilities requires that materials be hauled to the processing site. This is not always practical, especially when dealing with large amounts of waste dealt with in construction and in forest clearing or in instances, wherein individuals do not have access to vehicles which are adequate for hauling such waste materials.
In view of the foregoing, there have been numerous inventions directed to providing mobile chipping and shredding machines. Basic chipping and shredding units may be utilized by homeowners to process grass cutting, leaves, small branches and limbs, into a usable mulch material. Such shredding machines normally include a plurality of rotating blades mounted at the base of a receiving hopper. Material being fed into the blades is conveyed by a blower mechanism to bags appropriate piles. An example of such a machine is disclosed in U.S. Pat. No. 5,137,219 to Morey. Unfortunately, such small wood chipping machines are not adequate to shred larger or bulkier wood fiber material including logs, large limbs, tree roots, construction lumber and the like. Further, blower systems are inherently dangerous in that materials are discharged at considerable velocities and individuals can be struck by the debris being discharged.
Larger or more commercial portable wood shredding machines have been developed for processing heavy timber and large waste materials. Generally, such shredding machines either utilize fixed anvils which cooperate with rotating cutter blades or a plurality of intermeshing cutter blades to reduce the material being treated. In U.S. Pat. No. 3,822,042 to Roy, a demolition apparatus is disclosed which utilizes a plurality of cylindrical cutter elements which are generally aligned in a common plane. The material being processed passes from a hopper and between the cutting elements and is thereafter discharged vertically onto a conveying apparatus. Other examples of roller or auger cutters are disclosed in U.S. Pat. No. 4,938,426 to Koenig and German Patent 3 704 713 of Jul. 14, 1988.
An industrial type portable shredder having a fixed anvil and rotating cutter is disclosed in U.S. Pat. No. 4,773,600 to Metski. This patent discloses a trailered vehicle system for processing large portions of trees and tree stumps and includes a solid roller having a plurality of teeth embedded in the surface thereof. The teeth cooperate with fixed anvil teeth which extend inwardly from the housing surrounding the roller. The teeth on the roller cooperate with the teeth on the anvil to pulverize the material which is thereafter discharged to an underlying conveyor. The fixed anvil shredding system provides a benefit over other types of shredding systems in that the shredding auger or roller may be operated at extremely low rpm when compared to other systems. In the patent to Metski, it is stated that the cylinder on which the cutting teeth are mounted is operated under 50 rpm. This is compared with a more conventional rotation rate of other type cutting machines of 1500-1800 rpm. As discussed in the patent, by allowing the cylinder to rotate at lower rpm, damage to the teeth and other elements of the machine is significantly reduced, thereby decreasing downtime for maintenance and decreasing operating and repair costs.
Additional examples of prior art are disclosed in U.S. Pat. Nos 4,214,713 to Wright and U.S. Pat. No. 4,951,883 to Loppoli et al.